Crown and bridge work.



PATENTED APR. 24, 1906 A. H. BROWN;

CROWN AND BRIDGE WORK.

Inventor,

APPLICATION FILED SEPT. 18, 1905.

ArZfiurwmw/z,

Witne sses:

Attorneys.

UNITE STATS PATENT orrrcn.

CROWN AND BRIDGE WORK.

Specification of Letters Patent.

Patented April 24, 1906.

Application filed September 18, 1905. Serial No. 278,907.

To a whom it may (ZUI'LPITILI Be it known that I, ARTHUR H. Baowy, a citizen of the United States, residing at Hamilton, in the county of Caldwell and State of Missouri, have invented a new and useful Improvement in Crown and Bridge Work, of which the following is a specification.

This invention relates to crown and bridge work.

The objectof the invention is materially to improve upon existing modes of constructing crowns and bridges whereby practically all strain will be removed from the anchoring pins, resulting thereby in the production of work having greater stability and capable of producing higher artistic effect.

\Vith the above and other objects in view, as will appear as the nature of the invention is better Lllltltl'StUUd, the same consists in the novel manner of constructing crowns and bridges, as will be hereinafter fully described and claimed.

In the accompanying drawings, forming a part of this specification, and in which like charactersof referenceindicate corresponding parts, Figure 1 is a view in vertical section through an incisor constructed in accordance with the present invention. Fig. 2 is a perspective view of the same. Fig. 3 is a view in side elevation, exhibiting the retainer combined with the tooth. Fig. 4 is a view in vertical longitudinal section through a bicuspid constructed in accordance with the present invention. Fig. 5 is a View in perspective of the bicuspid shown in Fig. 4, exhibiting the construction of its lingual surface. Fig. 6 is a view in perspective, showing a bicuspid with a cap and dowel combined therewith and constructed in accordance with the present invention. Fig. 7 is a view in perspective of a retainer used in carrying the procedure into effect. Fig. 8 is a view in perspective of a denture, taken from the front and constructed in accordance with the present invention. Fig, 9 is a similar View taken from the rear of the denture shown in Fig. 8.

The tooth of the present invention has as much or more porcelain in it as the ordinary vulcanite tooth and has also headed pins to be used in crown and bridge work. It is, however, distinctly different from the ordinary vulcanite tooth and to such an extent that it could not be very successfully used as a vulcanite tooth, while a vulcanlte tooth could not be substituted for the present invention, inasmuch as the pins of necessity would have to be shorter and set well up under the shoulder, or what will hereinafter be termed the pressure-receiving surface.

In crowns or bridges in which facings are used the metal backing must be allowed to cover the occluding surface of the facing to insure it against breakage, and this necessitates an undesirable display of gold and, further, increases the expense of the operation by requiring a large amount of gold. The procedure of the present invention eliminates visible gold and reduces the amount required, thereby lessening both the expense and the work and time of construction. Furthermore, it renders unnecessary the subjection of the tooth to the heat necessary to effect soldering, whereby the danger of fracturing the tooth or of changing its color is eliminated. Further, by having the thin ineisal third of each of the anterior teeth devoid of metal backing there is secured a life-like translucent appearance that has heretofore been exceedingly difficult to obtain. Furthermore, in the present invention the stress or pressure is resisted by a novel pressure-receivmg surface or shoulder on the tooth, this being true of the incisors and cuspids, while the posterior teeth have two of the pressure-receiving surfaces as bases, leaving the pins simply to retain the tooth in this position. The tooth is therefore stronger from the fact that there is a greater bulk of porcelain and is of more spherical form.

Another feature of a bridge constructed in accordance with the present invention is thatthe lingual surface, by virtue of the retainer, which preserves the natural form of the tooth, presents a broad smooth surface exposed to the tongue.

The features of novelty that define this invention from the art are, first, the teeth being more bulky are stronger, and the fact that in all the. teeth the stress is received by a pressure-receiving surface and in the posterior teeth by two pressure-receiving surfaces makes the liability of fracture very remote; second, the ease, facility, and cheapness with which a crown or bridge may be made; third, the teeth are removed while soldering is being effected, thereby eliminating all danger of. cracking or of changing the color of the teeth. and as no drying out of the investment is necessar as with facings, the case may be quickly eated and instantly cooled. thereby materially shortening the operation; fourth, in a finished crown or bridge the incisal edge IIO of the tooth shows no gold and has life-like translucency, adding thereby greatly to the apearance of the teeth; fifth, in case of breakage another tooth may be fitted and the repair completed immediately and Without pain or annoyance.

Referring to the drawings and to Figs. 1, 2, and 3, 1 designates an lncisor the lingual surface of which is provided with a shoulder 2, constituting a pressure-receiving surface, which is dis osed approximately at right angles to the ength of the tooth and adjacent to which are disposed two anchoring-pins 3, that are preferably parallel with the shoulder and exactly at right angles to the flat lingual surface 4. The'gold-reta'iner 5 (shown in detail in Fig. 7) is provided with two opensided sockets 6, which are adapted to be engaged by the headed pins 3 and bears squarely against the shoulder, whereby the latter is caused 'to receive all of the pressure,

the pins merely serving to hold the retainer and tooth assembled. As usual, the retainer is held combined with the ins by cement that excludes moisture and insures firmness.

In the form of the invention-exhibited in Figseet, 5, and 6, wherein the pins are shown applied to a bicuspid, the latter is provided with two shoulders 7 and 8, the former being disposed at right angles to the ion th of the tooth and the latter obliquely wit relation" thereto. The shoulder 7 is enga ed b the retainer 5, as above described, an the s oulder 8 by a ortion of the base of the cap 9, as shown in ig. 6, the retainer and cap, as usual, being soldered together.

In the form of the invention shown in Figs. 8 and 9 the manner in which the brid e is constructed is exhibited, the bridged "teet 10 being soldered, asus'ual, to the two crowns 11, carr ing dowels or anchoring-posts 12. In this orm of .the-invention the manner of assembling the retainer with the teeth is the same as that described, the only difference being that bridgework is shown instead of mere 'crownwork, as in Fig. 6. In order to strengthen the sus ension 13, iridio-platinum wire 14 may be so dered to the bridge.

While the rocedures above described are confined to blcuspids, it is to be understood that they are equally adaptable forv use in connection with molars, and as this will be ap arent detailed illustration is omitted.

11 constructing a crown'according to the present invention the cap and dowel or cope are first made in the same manner as for a Richmond crown. An impression is then.

taken, themodel poured, and the tooth selected. .To the in 'val surface of the retainer is soldere with twenty-carat solder eraser is allowed to overlap the tooth slightly at the mesial and distal aspects. The retainer, with backing, is then placed in position -on the tooth and waxed in position on the co ing, no wax being allowed to adhere to t e tooth, but only to the retainer and backing. The tooth is then removed and the case invested, soldered, and then finished and is finally cemented in position. In the case of a bridge-tooth the same method of soldering a gold late to the retainer is observed, exce t that it need not extend under the tooth on y so far as it is desired to have the solder flow.

After the completion of the case the tooth is cemented in position in the manner described.

It will be seen from the foregoing description that when stress or pressure isapplied to a tooth or denture constructed in accordance displacement is secured.-

"Havingthus described the invention, what is claimed is- 1. A dentureem'bodying a retainer pro- ,vided in one edge with sockets dis osed wholly within it, and a tooth having a s oulder to engage the retainer and close the sockets and headed-pins to engage the sockets.

2. A denture embodying a tooth 'rovided with a flat pressure-receiving shou der disosed approximately at right angles to its ength and extending throu bout the width of the tooth and With'heade anchoring-pins extending parallel with the shoulder, and a retainer to be engaged'by the'shoulde'r and provided with sockets to be engaged. by the eaded ends of the pins.-

3. A denture comprising a tooth having its lingual surface provlded with two flat shoulders arranged in step order, one of which is disposed at right angles to the length of the tooth and the other obliquely thereto, a headejd retainer engaging one of the shoulders, and means-for assembling the tooth and retainer.

4. A denture comprising a toothxh'aving its lingual surface providedwith two fiat shoulders arranged in stepordenone ofwhiehis disposed at right angles to the len .th ofthe' tooth and. the other obliquely t ereto, a headed retainer engaging the first-named shoulder, and means for assembling the tooth and'the retainer.

In testimony that I claim the foregoing. as

my own I have hereto afiixed my signature in 

